1. Field of the Invention
The invention relates, in general, to a safety shield adapted for use with a syringe for protecting a needle after use in a medical procedure and, more particularly, to a safety shield adapted for extending to nearly twice the length of a syringe barrel to protect an extended length needle.
2. Description of Related Art
There is an ever-increasing need for the use of syringes having longer needles for completing specific medical procedures. The use of these longer needles is often necessary to ensure proper medication delivery. Along with the use of longer needles, a need has arisen for ways in which to properly shield these longer needles to prevent accidental needle sticks after completion of the procedure.
Shields for protecting needles after use in medical procedures are known. Such devices protect medical personnel from needle sticks after such needles have been used in a medical procedure. Different types of shields currently on the market include hinged shields which rotate 90-180 degrees to cover the needle, and spring activated shields which are actively or passively activated to extend through a needle hub to cover the needle. These designs are not concerned with long needle safety and may be too cumbersome to convert to use with a longer needle.
An example of a device for shielding a needle is shown in U.S. Pat. No. 6,869,415 to Asbaghi. This device includes a guard member that is restrained in a proximal position within a guide way. When a blood collection vial is engaged with the device, the guard member is automatically released to move distally over the needle as the needle is being withdrawn from the patient.
Another example of a shielding device currently in use is the SAFETY-LOK™ device available from Becton, Dickinson and Company, the Assignee of the current invention. In the SAFETY-LOK™ device, a cylindrical shield with an end cap is positioned around the barrel of a standard syringe. After the syringe is used for an injection, the shield is advanced forward by the user until it extends fully over the end of the needle and locks into place via a collar that is press-fit around the luer threads. U.S. Pat. No. 4,631,057 to Mitchell also shows a cylindrical shield which is positioned about the barrel of a syringe, which can be advanced forward after use of the needle. These existing devices are limited with respect to the length of a needle that can be protected because the shield can only be as long as the barrel of the syringe. Additionally, viewing of the graduated markings on the syringe barrel and/or the contents of the syringe barrel can be impaired due to the thickness and/or clarity of the shield when in the retracted position surrounding the barrel.
U.S. Pat. Nos. 7,147,624; 6,514,229; 6,080,135; 5,772,636; 5,336,199; 4,897,083; and 4,804,372 all show needle sheaths including multiple nested members mounted to a needle base. Upon the completion of a medical procedure, these nested members are expanded in a forward direction to cover the needle and protect the user from unwanted needle sticks. These devices are limited in needle length which can be covered because the nested devices can only have a certain thickness. Otherwise, the syringe can become difficult to handle.